Slide for photographic-plate holders.



PATENTED JULY 28, 1908.

L. BORSUM. SLIDE FOR PHOTOGRAPHIG PLATE HOLDERS,

APPLIG'ATION FILED AUG.9, 1907.

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LOUIS BQRSUBL OF PLAINFIELD, NEW JERSEY.

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4 I Application To all whom it may concern:

Be it known that I, LOUIS BORSUM, a citizen of the United States of America, residing at Plainfield,co1 1nty of Unibn, State of New Jersey,'have invented an Improved Slide for Photographic Plate Holders, of which the following'is a specification.

' Plate holder slides have heretofore been made of metal having a liquid coating, such as enamel, varnish or aint, applied thereto but in practice they ave beenunsatisfactory for the reason that bending of the slide will cause the coati to crack oil" or slight abrasion will expose t e surface of the metal. Moisture also tends to cause the coating. to peel off. Notwithstanding the desirability of metal slides on account of their thinness and strength they have met with a very limited success in practical use. As is Well understood, a very sli ht ex osure of the bright surface of metal wil fo t e sensitive plates.

To produce a desira le,: satisfactory plate holder slide of a thickness not noticeably greater, ifgreater at all, than the metal slides If the fabric is of the p mentioned, I place around a thin metal plate of appropriate size a thin fabric, such as paper or woven cloth, or silk, cotton or linen, and intimately unite the fabric to the plate by a suitable adhesive. The adhesive should preferably be such as will not be affected by moistureor by solutions ordinarily employed in the dark room and which not infrequently come in contact with the plate holder slidesi er black color and sufficiently opaque to entirely cover the surface of the rectal, it need not be specially treated after its application to the metal plate. with a water proofing solution such as black shellac, varnish or other a propriate mate rial which, when it has drie may be rubbed down to produce the desired dead surface. The fabric, whether paper or woven cloth, and the varnish or liquid that may be applied to it exteriorly should be photographically neutral with respect to the sensitized plate. Experience has demonstrated that such a plate holder slide is highly eflicient. It may e more or less elastic according to the metal employed and relativel considerable strength.

ver "thin and of ending of the slide will not cause detachment of the fabric nor of the superficial varnish or coating, when used;

' Specification. or L'ettersjatent.

I, however, by preference -coat\it Patented July as, race.

filed August a, 1907. Serial No. scares.

solutions in'uriously affect it. Such a slide is of very c eap construction and possesses allldthe desired requirements of a plate holder s 1 e.

Aluminum, on account of its lightness ,has

-to reinforce the metal with res ect to its rigidity and-elasticity so that I ave found in practice that the slides may be made uite as thin as it is feasible to make metal s ides nor will drops of water or of photographic The coztthaving applied directly to them varnish coatin s or enamels. I

n the accompanying drawing: Figure 1 is a perspective plan view of a plate holder slide constructed in accordance with my invention; Fig. 2,'an enlarged section on'the line. 2, 2, of Fig. l and Fig. 3, areduced face-view indicatin both'thefabric and the varnish or enamel-1i re coating. a is theor'dinaryhead or end iece of the slide; 6 the metal plate core; 0 t e a er or woven fabric within which the'm'eta' p ate is dis osed. v p a I v v n Fig. 3, 0? indicates the su erficial varnish coating, and c the fabric. n practice the varnish coating would be a phedover the entire surface of both sides 0 the slide.

. In Fig. 2, 0 indicates a lap-joint of the fabric which is. exaggerated for thepurpose of illustration. The 'oint would of course be substantially fiat w th the surface of the slide.

1 claim: i

1. A photographic late-holder slide comprising a thin metal s cot and fabric enveloping the sheet and intimately united therewith by adhesive material.

2. A photographic plate-holder slide comprising a thin sheet, fabric enveloping 'the sheet and intimately united therewith by adhesive material and a dried coating of var- Irish-like material applied tothg exterior of the fabric.

In testimony whereof, I-have hereunto sub= S. A. HASTIE, L. F. BROWNIN 

